Network Working Group R. Hinden
Request for Comments: 2928 Nokia
Category: Informational S. Deering
Cisco
R. Fink
LBNL
T. Hain
Microsoft
September 2000
Initial IPv6 Sub-TLA ID Assignments
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2000). All Rights Reserved.
Abstract
This document defines initial assignments of IPv6 Sub-Top-Level
Aggregation Identifiers (Sub-TLA ID) to the Address Registries. It
is intended as technical input to the Internet Assigned Numbers
Authority (IANA) from the Internet Engineering Task Force (IETF)
Internet Protocol Next Generation (IPNG) and Next Generation
Transition (NGTRANS) working groups, as an input to the process of
developing guidelines for the allocation of IPv6 addresses.
This document was originally developed to provide advice to IANA in
the fall of 1998 and is being published at this time for the
historical record. The Internet Architecture Board (IAB)
subsequently requested that the IANA delegate these assignments to
the Address Registries. The IANA did this and the Address Registries
are now using them to assign IPv6 addresses.
1. Introduction
This document was originally developed to provide advice to IANA in
the fall of 1998 and is being published at this time for the
historical record. The IAB subsequently requested that the IANA
delegate these assignments to the Address Registries. The IANA did
this and the Address Registries are now using them to assign IPv6
addresses.
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RFC 2928 Initial IPv6 Sub-TLA ID Assignments September 2000
This document defines initial assignments of IPv6 Sub-TLA Aggregation
Identifiers (Sub-TLA ID) to the Address Registries. It is intended
as technical input to the IANA from the IETF IP Next Generation
(IPNG) and Next Generation Transition (NGTRANS) working groups, as an
input to the process of developing guidelines for the allocation of
IPv6 addresses.
The IAB and IESG have authorized the Internet Assigned Numbers
Authority (IANA) as the appropriate entity to have the responsibility
for the management of the IPv6 address space as defined in [ALLOC].
The proposed initial assignment described in the document is
consistent with:
- RFC 2373,"IP Version 6 Addressing Architecture" [ARCH]
- RFC 2374 "An Aggregatable Global Unicast Address Format" [AGGR]
- RFC 2450 "Proposed TLA and NLA Assignment Rules" [TLA-RULES]
2. Background
[TLA-RULES] specifies that TLA assignments will be done in two
stages. The first stage is to allocate a Sub-TLA ID. This document
specifies the initial assignments of Sub-TLA ID's to the Registries.
As defined in [TLA-RULES] Section 5.1:
"Sub-TLA ID's are assigned out of TLA ID 0x0001 as follows. Note
that use of the Reserved field to create the Sub-TLA field is
specific to TLA ID 0x0001. It does not affect any other TLA.
| 3 | 13 | 13 | 19 |
+----+----------+---------+---------------+
| FP | TLA | Sub-TLA | NLA |
| | ID | | ID |
+----+----------+---------+---------------+
where:
FP = 001 = Format Prefix
This is the Format Prefix used to identify aggregatable global
unicast addresses.
TLA ID = 0x0001 = Top-Level Aggregation Identifier
This is the TLA ID assigned by the IANA for Sub-TLA
allocation.
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RFC 2928 Initial IPv6 Sub-TLA ID Assignments September 2000
Sub-TLA ID = Sub-TLA Aggregation Identifier
The Sub-TLA ID field is used by the registries for initial
allocations to organizations meeting the requirements in
Section 5.2 of this document. The IANA will assign small
blocks (e.g., few hundred) of Sub-TLA ID's to registries. The
registries will assign the Sub-TLA ID's to organizations
meeting the requirements specified in Section 5.2. When the
registries have assigned all of their Sub-TLA ID's they can
request that the IANA give them another block. The blocks do
not have to be contiguous. The IANA may also assign Sub-TLA
ID's to organizations directly. This includes the temporary
TLA assignment for testing and experimental usage for
activities such as the 6bone or new approaches like exchanges.
NLA ID = Next-Level Aggregation Identifier
Next-Level Aggregation ID's are used by organizations assigned
a TLA ID to create an addressing hierarchy and to identify
sites. The organization can assign the top part of the NLA ID
in a manner to create an addressing hierarchy appropriate to
its network."
Note: In the above quote from [TLA-RULES] the references to "Section5.2" refer to section 5.2 in [TLA-RULES].
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RFC 2928 Initial IPv6 Sub-TLA ID Assignments September 20008. Full Copyright Statement
Copyright (C) The Internet Society (2000). All Rights Reserved.
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Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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